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Rule of 72 Calculator

Calculate how long it takes for money to double at a given interest rate.

Annual interest rate or return

How many years to double your money

For visualization purposes

Rule of 72 Formula

Doubling Time = 72 ÷ Interest Rate

This is an approximation that works best for rates between 6% and 10%

Rule of 72 Results

Interest Rate: 0%
Doubling Time: 0 years
Exact Time: 0 years
Accuracy: 0%
Doubling Time: 0 years
Required Rate: 0%
Exact Rate: 0%
Accuracy: 0%

Growth Projection

Initial Amount: $0
After Doubling: $0
Total Growth: $0

Accuracy Note

Multiple Doublings

Doubling # Years Multiple Amount

Rule of 72 Applications

Investment Planning:

  • • Quick estimate of investment growth
  • • Compare different investment options
  • • Set realistic financial goals
  • • Understand compound interest power

Common Rates:

  • • 6% rate: ~12 years to double
  • • 8% rate: ~9 years to double
  • • 10% rate: ~7.2 years to double
  • • 12% rate: ~6 years to double

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Build v1.0.0.305714 • Sep 19, 2025, 02:15 PM EDT

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v1.0.0.305714